How to Use 3D Entity Snaps
Quick answer: Alongside the 2D entity snaps, BricsCAD has nine 3D entity snap modes for points on solids, surfaces, splines, and meshes. Which ones are active gets stored in 3DOSMODE as a bitcode, the sum of whichever modes are selected.
The Nine 3D Entity Snap Modes
| Mode | What it does |
|---|---|
| Center | Snaps to the centre of 3D faces |
| Intersection | Snaps to intersections of linear entities, edges, and polar or entity snap tracking lines with faces |
| Knot | Snaps to knots (fit points) on splines |
| Midpoint | Snaps to the midpoint of a face edge |
| Nearest | Snaps to whatever point on a 3D entity’s face is nearest to the cursor |
| None | Disables all 3D snap modes |
| Perpendicular | Snaps to a point perpendicular to a face on a 3D entity |
| Vertex | Snaps to the closest vertex of a 3D entity, and to control vertices of splines |
| Point Cloud | Snaps to a point cloud’s nearest point |
Setting 3D Entity Snap Modes
Any of these:
- Click a button on the 3D Entity Snaps toolbar (active modes show pressed).
- Run
3DOSNAPor-3DOSNAP. - Hold
Shift, right-click, hover over 3D Entity Snap in the context menu, and click the mode you want.
With no command running, clicking a toolbar button toggles that mode on or off. With a command running, clicking one instead sets it for just the next point, temporarily disabling every other selected mode while it’s used.
Frequently Asked Questions
How many 3D entity snap modes are there? Nine: Center, Intersection, Knot, Midpoint, Nearest, None, Perpendicular, Vertex, and Point Cloud.
What’s different about clicking a 3D snap mode while a command is running versus when nothing’s active? With no command active, it toggles that mode on or off as a running snap. With a command active, it applies just to the next point and temporarily disables every other selected mode.
Can 3D entity snaps snap to spline control points? Yes, the Vertex mode covers both the closest vertex of a 3D entity and the control vertices of splines. Knot mode is separate, and snaps to a spline’s fit points instead.
Where is the current set of active 3D snap modes stored? In the 3DOSMODE system variable, as a bitcode representing the sum of whichever modes are currently selected.